Many users subscribe to both wireless telephony services (e.g., cellular phone) and wired (i.e., wireline) telephony services such as plain old telephone service (POTS) and/or voice over Internet protocol (VoIP) service. Increasingly, subscribers desire a single telephone number that can automatically locate and follow the user. An example service sequentially routes a call via various telephony services, each usually having a different telephone number, in an attempt to locate the user. An example communication device is multi-mode and can be used to communicate via a variety of telephony technologies. For instance, some cellular phones can communicate via both cellular and wireless Internet-based technologies.